Thornton Fractional North High School (T.F. North, TF North, TFN) in Calumet City, Illinois first opened its doors in March 1926 as Thornton Fractional Township High School. The fully accredited school serves Calumet City & Burnham. T.F. North also serves over 1,700 students in grades 9-12. The school's boundaries are the City of Chicago on the North, Torrence Avenue on the West, the Indiana state line on the East, & the Little Calumet River to the South.